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Correspondence Between Oscillations and Emitted Photon Closed-Orbits in Spontaneous Emission Rate of an Atom Near a Dielectric Slab

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Communications in Theoretical Physics 2007年第5期47卷 887-891页

作者： YUN Su-Jun wang fu-he ZHOU Yun-Song DU Meng-Li Departrnent of Physics Capital Normal University. Beijing 100037 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China

We study the oscillations in the spontaneous emission rate of an atom near a dielectric slab. The emission rate is calculated as a function of system size using quantum electrodynamics. It exhibits multi-periodic oscillations. Four frequencies of the oscillations are extracted by Fourier transforms. They agree with actions of photon closed-orbits going away and returning to the atom. These oscillations are explained as manifestations of quantum interference effects between the emitted photon wave near the atom and the returning photon waves travelling along various closed-orbits.

关键词： quantum electrodynamics photon closed-orbit spontaneous emission Fourier transform

Cluster Model for p-Type Doping of ZnSe

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Chinese Physics Letters 1997年第7期14卷 528-530页

作者： REN Tian-ling ZHU Jia-lin XIONG Jia-jiong DUAN Wen-hui wang fu-he Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Chinese Academy of SciencesBeijing 100080

Cluster model with DV-Xαmethod is used to study the structural and electronic properties of the p-type doping of *** is found that there is Jahn-Teller distortion for P doping and almost no Jahn-Teller distortion for N doping,and that the impurity levels with respect to the maximum of valence band are 118 and 96meV for N and P doping,*** reasons why N can serve as a better dopant than P for p-type ZnSe are discussed.

关键词： ZnSe dopant doping

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng he Fan YANG Yafei wang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

Hydrogen sulfide facilitates carotid sinus baroreceptor activity in anesthetized male rats

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Chinese Medical Journal 2007年第15期120卷 1343-1347页

作者： XIAO Lin WU Yu-ming wang Ru LIU Yi-xian wang fu-wei he Rui-rong Department of Physiology Institute of Basic Medicine Hebei Medical Univesity Shijiazhuang 050017 China

Background It has been reported that hydrogen sulfide （H2S） could relax vascular smooth muscle by direct activation of KATP channels and hyperpolarization of the membrane potential. Recently, our study has shown that H2S facilitated carotid baroreflex. This study was conducted to investigate the effect of H2S on carotid baroreceptor activity （CBA）. Methods The functional curve of carotid baroreceptor （FCCB） was constructed and the functional parameters of carotid baroreceptor were measured by recording sinus nerve afferent discharge in anesthetized male rats with perfused isolated carotid sinus. Results H2S （derived from NariS） 25, 50 and 100 pmol/L facilitated CBA, which shifted FCCB to the left and upward. There was a marked increase in peak slope （PS） and peak integral value of carotid sinus nerve charge （PIV） in a concentration-dependent manner. Pretreatment with glibenclamide （20 pmol/L）, a KATP channel blocker, the above effects of H2S on CBA were abolished. Pretreatment with Bay K8644 （an agonist of calcium channels, 500 nmol/L） eliminated the role of H2S on CBA. An inhibitor of cystathionine y-lyase （CSE）, DL-propargylglycine （PPG, 200 pmol/L） inhibited CBA in male rats and shifted FCCB to the right and downward. Conclusions Our results suggest that exogenous H2S exerts a facilitatory role on isolated CBA through opening KATP channels and further closing the calcium channels in vascular smooth muscle. Endogenous H2S may activate CBA in vivo.

关键词： hydrogen sulfide potassium channels glibenclamide baroreceptors Bay K8644

NiTi(110)表面氧原子吸附的第一性原理研究

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物理学报 2017年第21期66卷 329-340页

作者：刘坤王福合尚家香首都师范大学物理系北京100048 北京航空航天大学材料科学与工程学院北京100191

为了研究给定的NiTi的表面氧化过程,在保持体系中Ni和Ti原子总数相等的条件下,构建了一系列Ti原子在表面反位的c(2×2)-NiTi(110)缺陷体系,并利用第一性原理计算研究了氧原子在各种NiTi(110)反位缺陷体系的吸附行为以及表面形成能.计算... 详细信息

为了研究给定的NiTi的表面氧化过程,在保持体系中Ni和Ti原子总数相等的条件下,构建了一系列Ti原子在表面反位的c(2×2)-NiTi(110)缺陷体系,并利用第一性原理计算研究了氧原子在各种NiTi(110)反位缺陷体系的吸附行为以及表面形成能.计算结果表明:吸附氧原子的稳定性与表面Ti原子的富集程度有很大的关联性,体系表面Ti原子富集程度越高,氧原子吸附的稳定性越高;当覆盖度较高时,由于氧原子的吸附,可使Ni和Ti原子在表面出现反位.在富氧条件(μ_o≥-9.35 eV)下,氧原子在表面第1层中的全部Ni原子与第3层全部Ti换位的反位缺陷体系上的吸附最稳定,此时随着氧原子的吸附,表面上的Ti原子升高,导致向上膨胀生长形成二氧化钛层,且在其下方形成富Ni层,由此可合理地解释实验上发现NiTi合金氧化形成二氧化钛层的可能原因.

关键词：第一性原理 NiTi合金二氧化钛表面能

SiO₂-SUPPORTED HRh（DPPE）₂ GATALYST

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Chinese Chemical Letters 1995年第6期6卷 517-518页

作者： Chang Ping SHAO Jie Yu wang and he fu GUO(Dalian Institute of Chemical Physics,Chinese Academy of Sciences Dalian 116023)

The catalytic behaviours of diO2-supported axh(DPPE)2 catalyst for CO hydrogenation and hydroformylation of propene were ***:The organophosphorus transition metal hydrides have been considered as active species for hydrogenation and hydroformylation of *** supported rhodium catalyst has been regarded as most effective for CO hydrogenation.2 here we re bort the catalytic behavof Sio2-supported HRH(DPPE)2(DPPE=l,2-bis(diphenylphosphino)-ethane).catalyst for GU hydrogenation and hydroformylation of ornene.

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SYNTheSIS　AND　CHARACTERIZATION　OF　Pt－M（M＝Cr，Mo，W）　heTEROBINUCLEAR　METAL　HYDRIDO　CARBONY　COMPOUNDS

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Chinese Chemical Letters 1994年第8期5卷 717-718页

作者： Chang Ping SHAO Jie Yu wang and he fu GUO(Dalian Institute of chemical Physics,Chinese Academy of Sciences,Dalian 116023)

The early-late transition metal heterobinuclear Pt-M(M=Cr,Mo,W)hydeido carbonal compounds were synthesized and characterized by IR and NMR spectroscopic means.

关键词： Pt OF CHARACTERIZATION Mo AND Cr

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song he Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Development of a Test Machine for IVECO Drive Axle

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International Journal of Plant Engineering and Management 2007年第1期12卷 24-28页

作者： wang Liang-mo wang he-fu CheN Jin-rong LING Zhi-liang CAO Yu-hua School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 P. R. China

To improve the automation level of the vehicle drive axle test and better simulate a vehicle＇s actual operation, an advanced test machine has been developed. The load system of the machine consists of hand brakes and electric cylinders. It is simple-structured and low-cost. The major motor of the machine is controlled by a transducer and its speed can be adjusted easily. In addition, the programmed machine can automatically test such parameters as the grinding condition, the differential speed, the noise level, etc. It can also adjust the test procedures according to different requirements. Detailed discussion of the structure and mechanism of the test machine is given in this paper.

关键词： vehicle test machine drive axle IVECO